package com.stxx.assistant.framwork.utils;

import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.UnknownHostException;
import java.util.Enumeration;

/**
 * @author Fuzhenlei
 * @date 2025/02/20 17:35
 */
public class HostUtils {
    public static Integer getPort() {
         return Integer.parseInt(System.getProperty("server.port"));
    }
    public static InetAddress getHost() throws UnknownHostException {
            try {
                InetAddress candidateAddress = null;
                // 遍历所有的网络接口
                for (Enumeration ifaces = NetworkInterface.getNetworkInterfaces(); ifaces.hasMoreElements();) {
                    NetworkInterface iface = (NetworkInterface) ifaces.nextElement();
                    // 在所有的接口下再遍历IP
                    for (Enumeration inetAddrs = iface.getInetAddresses(); inetAddrs.hasMoreElements();) {
                        InetAddress inetAddr = (InetAddress) inetAddrs.nextElement();
                        if (!inetAddr.isLoopbackAddress()) {// 排除loopback类型地址
                            if (inetAddr.isSiteLocalAddress()) {
                                // 如果是site-local地址，就是它了
                                return inetAddr;
                            } else if (candidateAddress == null) {
                                // site-local类型的地址未被发现，先记录候选地址
                                candidateAddress = inetAddr;
                            }
                        }
                    }
                }
                if (candidateAddress != null) {
                    return candidateAddress;
                }
                // 如果没有发现 non-loopback地址.只能用最次选的方案
                InetAddress jdkSuppliedAddress = InetAddress.getLocalHost();
                if (jdkSuppliedAddress == null) {
                    throw new UnknownHostException("The JDK InetAddress.getLocalHost() method unexpectedly returned null.");
                }
                return jdkSuppliedAddress;
            } catch (Exception e) {
                UnknownHostException unknownHostException = new UnknownHostException(
                        "Failed to determine LAN address: " + e);
                unknownHostException.initCause(e);
                throw unknownHostException;
            }
    }
}
